Delayed circuit-breaking light switch



March 25, 1930. c. B. JOHNSON DELAYED CIRCUIT BREAKING LIGHT SWITCH Filed N'UV. 25, 1929 INVENTOR amRLLsDJmmwN.

ATTORNEY Patented Mar. 25, 1930 be more pa My invention more partlcular owns 3. JOHNSON, or SEYMOUR, TEXAS DELAYE cinemas-B EAKING LIGHT SWITCH UNITED STATES: PATENT OFFICE l I Application filed November'25, 1929. Serial No. 409,710.

relates to light switches and spring metal and throu ly to delayed circuit breaking from the winding 12. The contact points 15 ht switches; and the object is to provide and 17 are normally hel a supplemental switch mechanism for prometal bars 16 and 18. longing the burning of a light after the main bar -18 is actuated by a switch has been turned 01f I means for automatically breaking the circuit 22 'ch is attached to t of the supplemental switch mechanism a short cont cts 15 and 17 are fter the main switch has been turned to off 10 and to provide rod 21 whic h is adapted point or detent 26 will from a base point of arm gh a wire 19 leading d apart by the spring To nfake contact the push-button on a 55 to bear on insulation he arm 18. When the brought together or contact made, they are temporarily locked in position. Such delayed switch is parcontact as follows :When ticularly desirable in bed-rooms and in many to contact making position, a catch or detent other rooms and olfices. Other objects and 23 will automatically lock the same. The deadvantages will be fully explained in the fol-- tent 23 is a two-pronged lever fulcrumed in a lowing description and the invention will bearing 24 which is mounted on and insulated rticularly pointed out in the snap behind the bar the bar 18 is pressed Q0 16 by insulation 25. 5 The engaging point 26 of the lever 23 normal- -Reference is had to the accompanying 1y rests against the contact bar 18. When ingswhich form a part of this applithe bar 18 is moved by the push button 20, the

switch.

Fig. 2 is a plan view of the same. ig. 3 1s a rear elevation.

Fig. 4 is a diagrammatic view of the wiring of both the standard and the improved switch. Fig. 5 is a detail view of the detent for holding the contacts locked for delaying the breaking of the circuit.

Similar characters of reference are used to l indicate the same parts throughout the several views.

This invention makes use of a block 1 of insulation and also a standard light switching mechanism including a switch lever 2 and 27 contact points 3 and 4 and current wires 5 and 6, .all of which may be inclosed in the regulation wall switch box 9. The improvement mechanism may also be inclosed in the "box 9. The improvement includes wires 10 and 11. The wire 10 is connected to a wind.

i-ng 12, of a thermostat 14 having the usual bi-mtallic bars of difl'erent co-eflicients of expansion and connected to the wire 6 which extends through the light globe 13. The wire 11 is connected to a light circuit on the opposite side of the master switch 2 from the wire connection 10. The wire-11 is connected electrically to a fixed contact 15 through a bar 16. The wire 10 is electrically connected to a movable' contact 17 through a bar 18 of- 20 Ifig. 1 is aside elevation of the improved 18 and thus hold the point 17 (carried by bar '10 other arm 29 which causes the point 26 to snap behind the bar 18. The contact points 15 and 17 are separated by the thermostat 14 Which carries and actuates a pull rod 30 which is mechanically connected to the detent 23, 30 which releases the bar 18 when actuated by the rod 30. The catch 26 is normally held against theedge of the bar l8'by the spring The improvement may be put in operating position, but will not operate until the main switch is 01?. When the main switch is turned off the light will remain on until the thermostat operates the improvement mechanism automaticallyto turn the light oil in a short period of time which period of time can be approximately predetermined. The resistance of'the' thermostat winding 12 prolongs the time for'operating the improvement, as may be determined.

he improvement will operate without turning on the main switch, by pushingthe button 20. The light will'be turned on, but

will last only until the thermostat causes the light to go out, as above described. 100

The main switch can be used as usual without being affected by the improvement because the improvement will not operate at all unless push button 20 is actuated.

With a given wattage line load, the time consumed in the delayingof the breaking of the circuit can be varied by varying the resistance of the winding of the thermostat.

With a given resistance of the windings on the thermostat, the greater the wattage load, or pull on the line from the socket represented with globe 13, in Fig. 4, the shorter the time consumed by the thermostat in effecting the final breaking of the circuit, and putting out of the light and vice versa. The delayed circuit breakingflight switch will make it possible for a pefson to place the light switch on off position and retire safely in bed,

or go out of the room, or leave a porch before the light goes out..

What I claim, is,

1. In an electrical lighting apparatus provided with a circuit and a switch Wires connected to said circuit on opposite sides of said.

switch, a fixed contact point connected to said circuit on one side of said switch, a movable. contact point and a spring bar carrying the same, a push-rod and a button carried thereby for actuating said spring bar for making contact with said contact points, a detent for automatically locking said points in contact and maintaining said contact, a thermostatic control electrically connected to said circuit on the other side. of said switch, and elec- 5 trically connected to said movable contact, and a pull-rod connected to said control and to said spring bar for breaking the contact.

2. Inan electric lighting apparatus provided with a circuit and a switch; wires con- 40 nected to said circuit on opposite sides of said switch, a fixed contact point'connected to one arm of said circuit, a movable contact and a spring-bar carrying the same, a pushrod and a button carried thereby for making contact of said points, a detent and a bearing therefor, a spring-arm carried by said detent adapted to engage said springbar automatically to maintain said points in contact, a thermostatic control electrically connected to the other arm of said circuit and to said movable contact, and a pull-rod operatively connected to said control and said spring-bar for automatically breaking said circuit.

In testimony whereof, I set my hand, this 17th day of November, 1929.

. CHARLES B. JOHNSON. 

